Air cushion craft air supply

ABSTRACT

A rigid base having air supplied directly thereunder is provided for each air cushion seal of the type customarily found on the periphery of air cushion craft or &#39;&#39;&#39;&#39;surface effect&#39;&#39;&#39;&#39; ships.

Muted States Patent 1191 Scltrinlr 1451 Dec. 31, 1974 [22] Filed:

[ AIR CUSHION CRAFT AlR SUPPLY [75] Inventor: John R. Schrink, Gautier, Miss.

[73] Assignee: Little Systems, Inc., Beverly Hills,

Calif.

Apr. 30, 1973 [21] Appl. No.: 355,509

Primary ExaminerKenneth H. Betts Assistant Examiner-.1ack D. Rubenstein Attorney, Agent, or Firm-Thomas A. Turner, .lr.;

[52] US. Cl 180/121, 180/123, 180/124 Al C R [51] Int. Cl. B60v 1/00 [58] Field of Search 180/116, 117,118, 119,

180/120, 121, 122, 123, 124, 125, 127, 128, [57] ABSTRACT 129 A rigid base having air supplied directly thereunder is provided for each air cushion seal of the type custom- [56] References Cited arily found on the periphery of air cushion craft or UNITED STATES PATENTS Surface effect 3,209,847 10/1965 Beardsley 180/128 5 Claims, 3 Drawing F igures D/REC T ION 0F TRAVEL I l I lb PATENTEB DEEB 1 I974 SHEET 1 BF 2 H 2 DIRECTION OF TRAVEL PATENIEUDEBB 1 I914 3'. e57, 456

SHEEI 2 BF 2 FIG? AIR CUSHION CRAFT AIR SUPPLY BACKGROUND OF THE INVENTION It has been known before to use air cushions to suspend a ship during transport above water, or perhaps land or marshy land. Such a vessel is conventionally known as an air cushion craft, hovercraft, or in the vernacular sometimes known as a surface effect ship." Conventionally, these surface effect ships are suspended on the air cushion, which is surrounded on the periphery by a skirt. Such skirts have been shown to be cellular in structure, as for example in US Pat. No. 3,631,938 to Eggington and in co-pending application, Ser. No. 355,510, filed Apr. 30, I973 simultaneously with this application. These skirts form a buffer on which waves, tall grass and other seaand marshimposed conditions react. Many problems have arisen when the wave or other shock-like condition strikes the skirt and the skirt fails to adjust in immediate response to the shock-like condition. The failure of the skirt to adequately respond to the shock-like condition, it is felt, has been cause of such air-suspended vessels plowingunder and capsizing, as several have done in recent years. Thus, it is important and urgently needed in the art to provide a cell'like air cushion craft skirt which will immediately, automatically and adequately respond to shock conditions which the sea or marshland presents to the craft.

SUMMARY OF THE INVENTION In a vessel of the air suspended type, a new pneumatic cushion cell arrangement is described having a rigid water contact sealing base. Air is forcibly supplied underneath the sealing base so that an air pocket exists between the sealing base and the water at least over a portion of the sealing base surface area.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a perspective view of the invention in its normal environment;

FIG. 2 illustrates a fragmentary side elevational view of the preferred embodiment of the invention;

FIG. 3 illustrates a plan fragmentary view of the invention in the preferred embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENT To achieve the desired end a new construction of a skirt 12 has been discovered for placement about the lower periphery of the conventional hovercraft or air suspended vessel 10, reference being had to FIG. 1. The air cushion 18 is held underneath the vessel by means of skirt 112 which surrounds the air cushion 18 on the periphery of the vessel 10. This skirt 12 can be constructed with cells at least on its bow and stem peripheral segments, as will be described in more detail below. Such new construction is explained and understood more clearly when FIG. 2, the view taken along line 22 in FIG. 1, is understood.

In FIG. 2, an air sealing cell 20 is shown depending below the forward edge periphery 16 of vessel 10. The cell 20 consists of flexible walls 22 which enclose a cell 20. The cells 20 are freely capable of vertical compression and extension. The walls 22 are disposed in airtight relationship with the underside of the periphery edge 16. The lower end of the cell is comprised of a rigid, sealing base which is in airtight coupling with the flexible walls 22. An orifice 32 is formed in the rigid base 30 so that air inside the cell and air between the rigid base 30 and the water surface 28 can freely pass through the rigid seal base 30. It may be desired to adjust the size of the orifice 32 so that the freedom of air passage therethrough can be restricted to a desired degree, thus creating a dampening effect. It may be desirable to form the orifice 32 having a horizontal overlap of the forward lip of the orifice to the rearward lip.

In the preferred embodiment as shown in FIG. 2, the rigid base is canted with the rearward end lower and in direct contact with the water level 28 so as to present an air planing surface to the water when the vessel 10 is in forward cruising speed.

It is contemplated that the cell 20 could be a single cell extending for the length of the periphery 16 in which the rigid seal base will be used. The cell 20 could be, however, a small ovalor rectangular-shaped cell. In such an event a plurality of such cells would be constructed in airtight, adjacent relationship along the periphery 16 of the air suspended craft. A rigid seal base 30 contact could be provided for each individual cell, or a single, common rigid seal base 30 could be posi tioned underneath adjacent cells.

If a series of adjacent cells 20 is utilized, the cells could be in pneumatic contact with each other or could be individually airtight and separate from one another. Air could be supplied to the cells either individually through separate conduits 52 as illustrated in FIG. 3, or, in the case of adjacent cells being pneumatically connected, by one air supply conduit.

Air under pressure will be supplied through conduit 40 from a compressor or pump 50. As shown in FIG. 2, conduit 40 supplies air directly to the underside of rigid base seal 30. Air pressure is trapped between rigid base seal 30 and the water level 28 by a flexible skirt 34 which depends from the forward edge of the rigid base seal 30. Some air will escape from this small air pocket forward underneath the skirt 34. A substantial amount of air will be forced from this air pocket through orifice 32 and into cell 20. It is in this manner that cell 20 will be inflated to cause the sealing of air cell 18 and the lift of the air suspended craft l0. Rigid seal base 30 may have its configuration varied so as to present a better planing surface to water. For example, it is contemplated that rigid base seal 30 could have a curved surface, or could have its forward end canted counterclockwise as in the description illustrated in FIG. 2.

It may be desired to construct conduit 40 of material having comparable flexibility to the flexible walls 22 of the cell. It is preferred, however, to construct the con duit 40 at least for that portion which will be within the confines of cell 20 of a rigid or semi-rigid material.-

Thus, when the air cell 20 compresses vertically, the rigid or semi-rigid conduit 40 portion within the cell will retract into the vessel 10. Otherwise, a flexible con duit 40 may have a tendency to fold over or otherwise collapse and present a blockage to the air being supplied to the air pocket.

In operation, air supplied under pressure is sent in the direction of the arrow shown in FIG. 2 through conduit 40. A small air pocket is developed between the rigid base seal 30 and the water level 28. The air is trapped within this pocket by the skirt 34, although some air should be expected to escape between the edge of skirt 34 and the water level 28. The rigid seal base 30 will always be in contact with the water, most probably at the rearward edge. Air within the pocket will flow through orifice 32 and into cell 20. The cell 20 begins to act as an air spring and to lift the air suspended craft 10. At this point, the air being supplied under pressure to the central cell 18 will then lift the vehicle and support it on an air cushion.

When the vessel 10 travels in the direction of the arrow as shown in FIG. 2, air and water waves will strike the cell 20 as indicated by arrows 44 in the drawing FIG. 2. Since the walls 22 of the cell 20 are flexible, as well as the skirt 34, the cell 20 will act as an air spring and will either retract or expand so as to accommodate the sudden shock of waves and the like. Maintaining the air pocket between the rigid base seal and the water level effectively prevents the forward edge of the rigid base seal from dipping below the water level 28. By always providing this air planing surface of rigid base seal to the water, the plowing-under which has occurred in the past will be eliminated.

I claim:

1. A vessel having a periphery about a hull and suspended upon a large, central air cushion during transport over a surface comprising:

a. at least one air cushion cell disposed depending from at least a bow section of said periphery forming a bow seal for said larger, central air cushion;

b. each said cell including a flexible wall and capable of vertical compression, and being fixed at its upper end to said periphery of said vessel;

c. each said cell further including a rigid base having an orifice therein for allowing air to pass therethrough, said rigid base disposed oriented at a planing angle relative to said surface, and having a portion of said rigid base in substantial contact with the said surface;

d. a chamber of air defined between the said surface and the lower side of said rigid base; and

e. air conduit means disposed in pneumatic contact beneath said rigid base with said chamber, said conduit means receiving air under pressure from a central air pressure source.

2. The vessel as claimed in claim 1, said cell further comprising a forward skirt disposed at the forward end of, and downwardly from said rigid base.

3. The vessel as claimed in claim 2, wherein said skirt is flexible and fixed to said forward end of said rigid base.

4. The vessel as claimed in claim 1 further including at least a second said air cushion cell disposed depending from at least a stern section of said periphery forming a stern seal for said central air cushion.

5. The vessel as claimed in claim 4 wherein said bow seal and said stern seal each comprise a plurality of smaller air cushion seals disposed in adjacent, airtight relationship. 

1. A vessel having a periphery about a hull and suspended upon a large, central air cushion during transport over a surface comprising: a. at least one air cushion cell disposed depending from at least a bow section of said periphery forming a bow seal for said larger, central air cushion; b. each said cell including a flexible wall and capable of vertical compression, and being fixed at its upper end to said periphery of said vessel; c. each said cell further including a rigid base having an orifice therein for allowing air to pass therethrough, said rigid base disposed oriented at a planing angle relative to said surface, and having a portion of said rigid base in substantial contact with the said surface; d. a chamber of air defined between the said surface and the lower side of said rigid base; and e. air conduit means disposed in pneumatic contact beneath said rigid base with said chamber, said conduit means receiving air under pressure from a central air pressure source.
 2. The vessel as claimed in claim 1, said cell further comprising a forward skirt disposed at the forward end of, and downwardly from said rigid base.
 3. The vessel as claimed in claim 2, wherein said skirt is flexible and fixed to said forward end of said rigid base.
 4. The vessel as claimed in claim 1 further including at least a second said air cushion cell disposed depending from at least a stern section of said periphery forming a stern seal for said central air cushion.
 5. The vessel as claimed in claim 4 wherein said bow seal and said stern seal each comprise a plurality of smaller air cushion seals disposed in adjacent, airtight relationship. 